If MTU will allow it, here ia a link that will settle all arguments in the thread.
http://www.vbulletin.com/docs/html
It shows how the points are earned and how they can be set.
It also states
User reputation can be a derisive element of your forum so great care should be taken before a decision is made to enable it. .
So you see Rep Power is an option that can be turned on or off and also be edited by the adminintrator of this website, MTU. This is right from the horses mouth
I could not edit the duplicate post because of a connection failure.